BUN /Creatinine Ratio : 296

Test Code

BCRAU or 296

Alias/See Also

Blood Urea Nitrogen; BUN

CPT Codes
82565, 84520

Transport Container

Preferred Specimen
2 mL serum

Alternative Specimen
Spun SST tube

Minimum Volume
1 mL

Transport Temperature

Room temperature.

Specimen Stability

Room temperature: 7 days; Refrigerated: 5 days; Frozen: 28 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Plasma

Methodology
See individual tests

Setup Schedule

Sunday - Saturday

Report Available

1 day

Reference Range

Urea Nitrogen (BUN)

Age Male Female

mg/dL mg/dL

<1 Month 4-12 3-17

1-11 Months 2-13 4-14

1-3 Years 3-12 3-14

4-19 Years 7-20 7-20

≥20 Years 7-25 7-25

Creatinine

Age Male Female

(mg/dL) (mg/dL)

≤2 days 0.79-1.58 0.79-1.58

3-27 days 0.35-1.23 0.35-1.23

1 month-9 years 0.20-0.73 0.20-0.73

10-12 years 0.30-0.78 0.30-0.78

13-15 years 0.40-1.05 0.40-1.00

16-17 years 0.60-1.20 0.50-1.00

18-29 years 0.60-1.2 4 0.50-0.96

30-39 years 0.60-1.26 0.50-0.97

40-49 years 0.60-1.2 9 0.50-0.99

50-59 years 0.70-1.30 0.50-1.03

60-69 years 0.70-1.3 5 0.50-1.05

70-79 years 0.70-1.28 0.60-1.00

≥80 years 0.70-1.22 0.60-0.95

For patients >49 years of age, the upper reference limit for creatinine is approximately 13% higher for people identified as African-American.

eGFR ≥60 mL/min/1.73m2

Bun/Creatinine Ratio 6-22 (calc)

Clinical Significance

The BUN/Creatinine ratio is useful in the differential diagnosis of acute or chronic renal disease. Reduced renal perfusion, e.g., congestive heart failure, or recent onset of urinary tract obstruction will result in an increase in BUN/Creatinine ratio. Increased urea formation also results in an increase in the ratio, e.g., gastrointestinal bleeding, trauma, etc. When there is decreased formation of urea as seen in liver disease, there is a decrease in the BUN/Creatinine ratio. In most cases of chronic renal disease the ratio remains relatively normal.

Performing Laboratory
med fusion

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.